Czechs
in the industrial centres of the Highland Banat were settled in the
18th and 19th c. together with the 'Austrians' there, who actually
assimilated them almost completely by the First World War. The Czech
villages in the southern Banat were colonised in two successive waves
in the first half of the 19th c., being border guard villages of the
Military Frontier. This colonisation was the same as that of the
'Austrian' villages in the Semenic Mountains ( Gărâna /
Wolfsberg, Brebu Nou / Weidenthal, Lindenfeld, Sadova Veche /
Alt-Sadowa, Caransebeșu Nou / Neu-Karansebesch / Schwabendorf ),
where Bohemian Germans were settled. In the Czech villages were
settled Czechs from the same areas, but occasionally also Germans.
Both groups are known as 'pemi' or, in Czech, 'pémové' ( from
German 'Böhmen', 'Bohemians' ). In a third wave, in the mid 19th c.,
smaller Czech populations were settled throughout already-existing
villages: Clopodia / Klopotýn, Peregu Mare, Scăiuș, Jupa.
There are also Czech villages in the Serbian Banat. The vast majority
of Czechs are Roman Catholics, but Reformed were also colonised, in Peregu Mare, Clopodia / Klopotýn and Sfânta Elena / Svatá Helena; those in
Clopodia emigrated before 1900, whereas those in Sfânta Elena have
converted to Baptism. Besides some Moravian settlers ( e.g. in
Clopodia ), they are only Bohemians, especially from SW Bohemia ( the
Plzeň / Pilsen and Klatovy / Klattau area ).

See
below the maps corresponding to the preceding post, for 1869 and
2002. Blue = at least 75%, green = 50-74%, yellow = 25-49%,
red-orange = 10-24%, turquoise = 4-9%. I have also included the two
villages in the Serbian Banat in the 2002 map ( Serbian census the
same year ).
Sources: http://www.kia.hu/konyvtar, http://webrzs.stat.gov.rs/WebSite/Default.aspx.